Predictors of Long-Term Survival in Pancreatic Ductal Adenocarcinoma after Pancreatectomy: TP53 and SMAD4 Mutation Scoring in Combination with CA19-9

BACKGROUND

Pancreatic ductal adenocarcinoma (PDA) is a fatal cancer for which even unfavorable clinicopathological factors occasionally fail to preclude long-term survival. We sought to establish a scoring system that utilizes measurable pre-intervention factors for predicting survival following surgical resection.

METHODS

We retrospectively analyzed 34 patients who died from short-term recurrences and 32 long-term survivors among 310 consecutively resected patients with PDA. A logistic regression model was used to define factors related to clinical parameters, molecular profiles of 18 pancreatic cancer-associated genes, and aberrant expression of major tumor suppressors.

RESULTS

Carbohydrate antigen 19-9 (CA19-9) had the best ability to classify patients with short-term recurrence and long-term survivors [odds ratio 21.04, 95% confidence interval (CI) 4.612-96.019], followed by SMAD4 and TP53 mutation scoring (odds ratio 41.322, 95% CI 3.156-541.035). Missense TP53 mutations were strongly associated with the nuclear expression of p53, whereas truncating mutations were associated with the absence of nuclear p53. The former subset was associated with a worse prognosis. The combination of aberrant SMAD4 and mutation types of TP53 exhibited a better resolution for distinguishing patients with short-term recurrences from long-term survivors (compared with the assessment of the number of mutated KRAS, CDKN2A, TP53, and SMAD4 genes). Calibration of mutation scores combined with CA19-9 in a logistic regression model setting demonstrated a practical effect in classifying long survivors and patients with early recurrence (c-statistic = 0.876).

CONCLUSIONS

Genetic information, i.e., TP53 mutation types and SMAD4 abnormalities, combined with CA19-9, will be a valuable tool for improving surgical strategies for pancreatic cancer.

A rare case of localized IgG4-related sclerosing cholecystitis mimicking gallbladder cancer

Objective: IgG4-related sclerosing cholecystitis is generally associated with IgG4-related sclerosing cholangitis and presents with diffuse, circumferential thickening of the gallbladder wall. We report a rare case of localized IgG4-related sclerosing cholecystitis without IgG4-related sclerosing cholangitis, which was difficult to differentiate from gallbladder cancer preoperatively. Patient: A 56-year-old man with suspected IgG4-related disease or gallbladder cancer was admitted to our ward. The serum IgG4 level was elevated at 721 mg/dL. Computed tomography (CT) demonstrated focal wall thickening of the gallbladder fundus. Drip infusion cholecystocholangiography with CT revealed no dilation, stenosis, or border irregularity of the bile duct. Results: For diagnostic and treatment purposes, cholecystectomy with wedge resection of the gallbladder bed was performed. The pathological diagnosis was IgG4-related sclerosing cholecystitis. Conclusion: It is difficult to differentiate IgG4-related sclerosing cholecystitis from gallbladder cancer in cases involving localized thickening of the gallbladder wall. In similar cases, surgical resection with cancer in mind might be performed based on present clinical knowledge.